Functional Subsets Research Articles

IL-7 Promotes the Expansion of Circulating CD28- Cytotoxic T Lymphocytes in Patients With IgG4-Related Disease via the JAK Signaling.

ObjectivesThis study aimed to elucidate the changes and associated mechanisms of circulating CD28- cytotoxic T lymphocytes (CTLs) in patients with IgG4-related disease (IgG4-RD).MethodsFifty IgG4-RD patients and 15 healthy controls (HCs) were recruited. Peripheral blood mononuclear cells (PBMCs) were isolated, the levels of circulating CD28- CTLs were detected by flow cytometry, and the proportions of CD127lo or GZMB+CD28- CTL subsets were analyzed in the meantime. Mechanistically, PBMCs isolated from IgG4-RD patients were stimulated with IL-7 in the presence or absence of the JAK inhibitor tofacitinib. Flow cytometry was used to analyze the proliferation of CD28- CTLs and the changes in related subpopulations.ResultsCirculating CD4+CD28- CTLs and CD8+CD28- CTLs were significantly increased in IgG4-RD patients compared with HCs, accompanied by an elevation of CD127lo or GZMB+ CTL subsets. The ex vivo culture of PBMCs showed that IL-7 could induce the amplification of CD4+CD28- CTLs and CD8+CD28- CTLs in IgG4-RD. Furthermore, IL-7 promotes the proliferation and functional subset changes of these CD28- CTLs in this disease. The selective JAK inhibitor tofacitinib significantly inhibited the effects of IL-7 on CD4+CD28- CTLs and CD8+CD28- CTLs.ConclusionIL-7 can affect the immune balance of IgG4-RD patients by promoting the expansion and function of CD4+CD28- and CD8+CD28- CTLs in IgG4-RD through the JAK pathway. Blockade of the IL-7 signaling pathway may be a new therapeutic strategy for IgG4-RD.

Dragon 1 Protocol Manuscript: Training, Accreditation, Implementation and Safety Evaluation of Portal and Hepatic Vein Embolization (PVE/HVE) to Accelerate Future Liver Remnant (FLR) Hypertrophy

Study PurposeThe DRAGON 1 trial aims to assess training, implementation, safety and feasibility of combined portal- and hepatic-vein embolization (PVE/HVE) to accelerate future liver remnant (FLR) hypertrophy in patients with borderline resectable colorectal cancer liver metastases.MethodsThe DRAGON 1 trial is a worldwide multicenter prospective single arm trial. The primary endpoint is a composite of the safety of PVE/HVE, 90-day mortality, and one year accrual monitoring of each participating center. Secondary endpoints include: feasibility of resection, the used PVE and HVE techniques, FLR-hypertrophy, liver function (subset of centers), overall survival, and disease-free survival. All complications after the PVE/HVE procedure are documented. Liver volumes will be measured at week 1 and if applicable at week 3 and 6 after PVE/HVE and follow-up visits will be held at 1, 3, 6, and 12 months after the resection.ResultsNot applicable.ConclusionDRAGON 1 is a prospective trial to assess the safety and feasibility of PVE/HVE. Participating study centers will be trained, and procedures standardized using Work Instructions (WI) to prepare for the DRAGON 2 randomized controlled trial. Outcomes should reveal the accrual potential of centers, safety profile of combined PVE/HVE and the effect of FLR-hypertrophy induction by PVE/HVE in patients with CRLM and a small FLR.Trial RegistrationClinicaltrials.gov: NCT04272931 (February 17, 2020). Toestingonline.nl: NL71535.068.19 (September 20, 2019).

Inflammatory Cytokine-Neutralizing Antibody Treatment Prevented Increases in Follicular Helper T Cells and Follicular Regulatory T Cells in a Mouse Model of Arthritis.

BackgroundFollicular T helper (TFH) and follicular regulatory T (TFR) cells play important roles in humoral immunity. Nevertheless, their significance in rheumatoid arthritis (RA) pathogenesis has not been fully elucidated. As an important treatment strategy, the effect of inflammatory factor-neutralizing antibodies on TFH and TFR in RA remains unclear.MethodsWe used the collagen-induced arthritis (CIA) mouse model to illustrate the quantity and functional changes in TFH and TFR cells. The changes of plasmablast, TFH and TFR cells in the spleen and peripheral blood of CIA mice were analyzed by flow cytometry. The levels of TFH and TFR and their functional subsets in the spleen after anti-inflammatory antibody treatment were analyzed and compared. The functional changes of TFH and TFR in CIA mice before and after treatment were detected by in vitro culture experiments.ResultsPlasmablast levels were increased in CIA spleen and peripheral blood and both TFH and TFR cell levels were upregulated. TFH and TFR cells were decreased significantly after the anti-inflammatory antibody treatment. TIGIT+ and TIGIT+CD226− TFH cells in CIA mouse spleen were elevated and PD-1 and ICOS expression on spleen TFH and TFR cells was increased. Both the ability of TFH cells to secrete IL-21 and aid B cells and the ability of TFR cells to secrete IL-10 and inhibit TFH cells were enhanced in the CIA mice. After antibody treatment, the cell subsets and functions were recovered.ConclusionGerminal center TFH and TFR cells were increased and their functions were enhanced. With inflammatory factor-neutralizing antibody treatment, TFH and TFR subsets and their functions returned to normal. These findings provide important information on the dynamics of humoral immune-related cell subsets in RA and the effects of treatment on them.

Kinetics of immune activated T cells in aplastic anemia mouse model

目的探索再生障碍性贫血（AA）小鼠模型中供者来源T细胞不同时间点动力学变化。方法构建AA小鼠模型，分别于不同时间点采用流式细胞术测定模型小鼠脾脏与骨髓内供者T细胞比例、活化分子表达、细胞周期及功能亚群，评估不同时期T细胞功能状态。结果①半致死剂量照射联合主要组织相容性抗原（MHC）半相合的淋巴结细胞输注成功构建T细胞免疫介导的AA小鼠模型。②AA小鼠脾脏中供者T细胞从移植第3天后开始明显浸润，并逐渐出现CD4+/CD8+比例倒置，第5天开始进入骨髓，以CD8+细胞浸润为主。③CD69在供者CD4+细胞中表达高峰晚于CD8+细胞，CD25在CD4+细胞与CD8+细胞中表达水平的变化趋势相同，但在CD8+细胞中的表达高于CD4+细胞。④脾脏内供者CD4+细胞S/G2/M期比例在移植后第3天即达高峰，约12％，而CD8+细胞中S/G2/M期比例在移植后第5天达高峰，约20％，且两者在进入骨髓后S/G2/M期比例均再次升高，但移植第3天后其比例在脾脏与骨髓CD8+细胞中持续高于CD4+细胞。⑤脾脏内免疫活化的T细胞经历短暂的中枢记忆T细胞（TCM）阶段后迅速分化为效应记忆T细胞（TEM），进入骨髓后部分TEM分化为效应细胞进一步发挥效应功能。结论AA小鼠模型中供者T细胞进入异体后迅速活化，5天内达增殖高峰，并完成向TEM细胞的分化，5天后开始进入骨髓进一步增殖损伤造血。

KVMIveggur: Flexible, secure, and efficient support for self-service virtual machine introspection

Virtual machine introspection (VMI) has evolved into a widely used technique for purposes such as digital forensics, intrusion detection, and malware analysis. The recent integration of enhanced VMI capabilities into KVM further facilitates the use of VMI. A significant obstacle, however, remains: VMI usually requires highly privileged access to the host system. Existing research prototypes that address this issue either target only the Xen hypervisor, are extremely slow, offer only a subset of the desired functionality, or are hard to deploy in real-life systems. We present our flexible KVMIveggur architecture as a novel solution to these challenges. It offers three flavors of isolation (using containers, virtual machines, and network remote access) that all enable access control for secure self-service VMI in cloud environments. It enables the full use of passive and active VMI, supports continuous monitoring also during live VM migration, and can be tailored for low overhead and minimal resource utilization on the host system. The experimental evaluation of our prototype demonstrates the feasibility and the efficiency of our approach and provides detailed insights into the differences between the three flavors.

S172: FUNCTIONAL SUBSETS OF PLASMA CELLS ASSOCIATED WITH AMYLOID PRODUCTION AND

S172: FUNCTIONAL SUBSETS OF PLASMA CELLS ASSOCIATED WITH AMYLOID PRODUCTION AND

Abstract 1537: Understanding role of uniquely enriched RNAs carried in non-small cell lung cancer derived extracellular vesicles and dynamics of their selective export

Abstract The dynamic interaction mediated by extracellular vesicles (EVs) between cancer cells and microenvironment has been shown to regulate cancer progression. Specifically, tumor derived EVs alter the phenotypes of recipient cells by delivering functional biomolecules including RNAs (EV-RNA). Studies from our lab reveal the impact of NSCLC derived EVs (Calu6 and H358) in promoting invasion of non-tumorigenic cells (BEAS-2B) and disruption of an epithelial barrier. We further determined that of all the major macromolecules contained in EVs, EV-RNA is a significant contributor to the observed phenotypes. Additionally, our data supports dysregulation of RNA subsets enclosed in NSCLC cell-derived EVs in comparison with non-tumorigenic EVs. Interestingly, RNA sequencing analysis revealed preferential enrichment of several small RNAs (<200nt), especially miRNAs, in EVs isolated from NSCLC cell lines which suggest the presence of precise mechanisms involved in loading and export of RNAs into EVs. We shortlisted a cohort of uniquely enriched miRNAs in EVs derived from Calu6 and H358 cell lines to understand their combinatorial effects on non-tumorigenic recipient cells. Amongst the shortlisted candidates miR-100, miR-10b, miR-21, miR-155 and miR-486 stand out as potential contributors to NSCLC-EV mediated function. To understand the dynamics of export of miRNAs into EVs, we transfected Calu6 cells with one of the uniquely enriched fluorescently labelled candidate miRNA (miR-451) and tracked its export into EVs. We first verified that inclusion of a fluorophore to the RNA does not impair RNA loading into EVs. To set the experiment up, one EV-enriched RNA and one Cell-enriched RNA (as a control) conjugated with different fluorophores were transfected into cells, and cellular and EV fluorescence were monitored. Interestingly, cellular fluorescence corresponding to the EV-enriched RNA diminished, while fluorescence corresponding to the Cell-enriched RNA was retained. Fluorescence signal for EV-enriched RNA showed retention in EVs isolated 48 hours after transfection. Validation of release of candidate miRNA into EVs was performed by inhibiting biosynthesis of EVs after treatment with nSMase inhibitor Gw4869. Inhibition of EV release caused EV-enriched RNA to be retained by the cells which was confirmed following flow cytometry analysis of treated cells. Despite clear evidence that dysregulated EV-RNA subsets enclosed in cancer cell-derived EVs can modulate the cellular microenvironment, research showing dynamics and mechanisms of their export is limiting. Hence, there is a critical need to reveal mechanistic details of RNA export into EVs. Resulting data from this study is expected to not only reveal functional EV-RNA subsets and dynamics of their loading but will ultimately point to novel targets for future therapeutic intervention. Citation Format: Humna Hasan, Nadia A. Lanman, Sagar Utturkar, Andrea L. Kasinski. Understanding role of uniquely enriched RNAs carried in non-small cell lung cancer derived extracellular vesicles and dynamics of their selective export [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1537.

Comparison of Peripheral Blood Regulatory T Cells and Functional Subsets Between Ocular and Generalized Myasthenia Gravis.

PurposeThis study aims to discuss the function mechanism of regulatory T cells and its subsets in the pathogenic process of myasthenia gravis by contracting the activation levels of those cells in peripheral blood among healthy people, patients with ocular myasthenia gravis (oMG) and patients with generalized myasthenia gravis (gMG).MethodHealthy people, newly diagnosed oMG patients, and gMG patients were enrolled in this study. The percentage of the CD3+CD4+CD25+ Treg cells, CD3+CD4+CD25+Foxp3+ Treg cells, CD3+CD4+CD25+Foxp3hi CD45RA–aTreg cells, CD3+CD4+CD25+Foxp3loCD45RA–n-sTreg cells, and CD3+CD4+CD25+ Foxp3loCD45RA+rTreg cells in the peripheral blood were examined by flow cytometry. And then analyzed the differences of Treg cells and its subsets among the study members.ResultsThe percentage of the CD4+CD25+Treg cells in the peripheral blood of oMG patients and gMG patients were both lower than that of healthy people (p < 0.05), the percentage of patients with oMG had no distinct difference with that of patients with gMG (p = 0.475), however. Also, the percentage of CD3+CD4+CD25+Foxp3+Treg cells in the oMG and gMG patients’ group were both lower than that of healthy group. And the percentage of CD25+Foxp3+Treg cells in the peripheral blood of patients with oMG and healthy people were both higher than that of patients with gMG (p < 0.05). The percentage of rTreg in the CD3+CD4+CD25+Treg of the peripheral blood for both gMG and oMG patients’ group were lower than healthy group (p < 0.05), but there was no statistical significance between the oMG and gMG patients’ group (p = 0.232). The percentage of the aTreg cells in the CD3+CD4+CD25+Treg cells of the peripheral blood for the oMG patients was higher than that of gMG patients (p < 0.05), but both of them were lower than healthy group (p < 0.05). The percentage of n-sTreg cells in the peripheral blood descended among the gMG patients’ group, oMG patients’ group, and healthy group (p < 0.05).ConclusionThe changes in the number and function of Treg cells and its subsets can cause the impairment of negative immune regulation, which may mediate the triggering of oMG and its progression to gMG.

Multiplex Immunofluorescence reveals specific subsets of immune cell populations expressing CD137/TNFRSF9 as predictors of unfavorable outcomes in Hodgkin Lymphoma

The tumor microenvironment (TME) is a crucial determinant of tumor growth, progression, and resistance to chemotherapy in cancer, with classical Hodgkin's lymphoma (cHL) being one of the most representative examples. The major component of the tumor mass in cHL is a rich and vast immune microenvironment, comprising a diverse repertoire of cell populations, many of which remain unknown. The specific contribution of the different functional cell subsets in the TME, such as T lymphocytes, monocytic populations, or dendritic cells, is also undiscovered. Currently, around 30% of advanced-disease patients or some atypical cases of primary refractory tumors do not respond to treatment or relapse shortly afterwards. Response predicting features of TME have been recently identified, which suggest a rationale for alternative therapeutic strategies. All existing evidence indicates that HRS cells actively coordinate and remodel their complex TME and that its diverse components influence the therapeutic response in cHL patients. The sensitivity of current technology enables analysis of specific functional phenotypes in the TME as diagnostic and predictive biomarkers. One example is the quantitative dissection of the TME with in situ multispectral imaging using formalin-fixed, paraffin-embedded (FFPE) tissues, with which we could analyze simultaneously CD68, CD137, CD30, CD3, PDL1, and PD1 markers to identify specific cell subsets. Remarkably, some cell populations expressing CD137 were associated with unfavorable responses in cHL patients, such as the activated monocytic cells (CD68+ CD137+), the tumor-reactive T cells (CD3+ CD137+), and the tumor CD30+ CD137+ PDL1+ cell subset. By contrast, the CD3+ CD137- T-cell population was associated with better prognosis, suggesting that CD137 could be a new prognostic marker in cHL for poor outcomes. Moreover, some cell subsets that could not be studied until now due to the lack of appropriate technology were found to be more abundant in the first stages of the disease, whereas others were less abundant than in stage IV. For instance, we could study exhausted T cells (CD3+ PD-L1+ PD-1+) and other related cells that were largely unexplored in cHL. Finally, these findings were validated with independent series of patient samples, including immunohistochemical studies with specific antibodies and gene-expression analysis.

Heterogeneous FPGA Architecture Using Threshold Logic Gates for Improved Area, Power, and Performance

The flexibility of field-programmable gate arrays (FPGAs) is attributed to the reconfigurability of their basic logic elements (BLEs). Traditionally, the BLEs are comprised of one or more lookup tables (LUTs) of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$n$ </tex-math></inline-formula> inputs, that are designed to implement Boolean functions of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$n$ </tex-math></inline-formula> or fewer inputs. In an attempt to reduce the area and power consumption that comes from using LUTs, a number of complex LUT architectures have been reported. Although most of the proposed complex LUT architectures have resulted in reduced area and power, this has always been at cost of the decreased performance. This article proposes a new FPGA architecture, called threshold logic FPGA (TLFPGA), which results in significant improvement in performance, power, and area (PPA). TLFPGA is comprised of a combination of LUTs and a new type of BLE referred to as a threshold logic cell (TLC) (Muroga, 1987). Although TLCs implement a relatively small subset of Boolean functions known as threshold functions (Muroga, 1987), they require far fewer registers and multiplexers than an LUT, and are also significantly faster. This article describes the architecture of the TLFPGA and a technology mapping algorithm tailored for a TLFGA. On average, TLFPGA designs use 18% fewer registers and multiplexers, which improves the collective area of BLEs by approximately 16%, power by 14%, and performance by 5%. The improvements have been demonstrated in both 40 and 28 nm technologies for ISCAS-85 circuits as well as practical circuits, using industry-standard flows. The improvements were also demonstrated using a layout of the architecture.

Approximating Continuous Functions on Persistence Diagrams Using Template Functions

The persistence diagram is an increasingly useful tool from Topological Data Analysis, but its use alongside typical machine learning techniques requires mathematical finesse. The most success to date has come from methods that map persistence diagrams into vector spaces, in a way which maximizes the structure preserved. This process is commonly referred to as featurization. In this paper, we describe a mathematical framework for featurization called template functions, and we show that it addresses the problem of approximating continuous functions on compact subsets of the space of persistence diagrams. Specifically, we begin by characterizing relative compactness with respect to the bottleneck distance, and then provide explicit theoretical methods for constructing compact-open dense subsets of continuous functions on persistence diagrams. These dense subsets—obtained via template functions—are leveraged for supervised learning tasks with persistence diagrams. Specifically, we test the method for classification and regression algorithms on several examples including shape data and dynamical systems.

The impact of phosphorylated PTEN at threonine 366 on cortical connectivity and behaviour.

The lipid phosphatase PTEN (phosphatase and tensin homologue on chromosome 10) is a key tumour suppressor gene and an important regulator of neuronal signalling. PTEN mutations have been identified in patients with autism spectrum disorders, characterized by macrocephaly, impaired social interactions and communication, repetitive behaviour, intellectual disability, and epilepsy. PTEN enzymatic activity is regulated by a cluster of phosphorylation sites at the C-terminus of the protein. Here, we focused on the role of PTEN T366 phosphorylation and generated a knock-in mouse line in which Pten T366 was substituted with alanine (PtenT366A/T366A). We identify that phosphorylation of PTEN at T366 controls neuron size and connectivity of brain circuits involved in sensory processing. We show in behavioural tests that PtenT366/T366A mice exhibit cognitive deficits and selective sensory impairments, with significant differences in male individuals. We identify restricted cellular overgrowth of cortical neurons in PtenT366A/T366A brains, linked to increases in both dendritic arborization and soma size. In a combinatorial approach of anterograde and retrograde monosynaptic tracing using rabies virus, we characterize differences in connectivity to the primary somatosensory cortex of PtenT366A/T366A brains, with imbalances in long-range cortico-cortical input to neurons. We conclude that phosphorylation of PTEN at T366 controls neuron size and connectivity of brain circuits involved in sensory processing and propose that PTEN T366 signalling may account for a subset of autism-related functions of PTEN.

Lineability, spaceability, and latticeability of subsets of C([0, 1]) and Sobolev spaces

This work is a contribution to the ongoing search for algebraic structures within a nonlinear setting. Here, we shall focus on the study of lineability of subsets of continuous functions on the one hand and within the setting of Sobolev spaces on the other (which represents a novelty in the area of research).

The accumulation of V\u03b34 T cells with aging is associated with an increased adaptive V\u03b34 T cell response after foodborne Listeria monocytogenes infection of mice

BackgroundIt is generally accepted that aging has detrimental effects on conventional T cell responses to systemic infections. However, most pathogens naturally invade the body through mucosal barriers. Although mucosal sites are highly enriched in unconventional immune sentinels like γδ T cells, little is currently known about the impact of aging on unconventional mucosal T cell responses. We previously established that foodborne infection with a mouse-adapted internalin A mutant Listeria monocytogenes (Lm) generates an adaptive intestinal memory CD44hi CD27neg Vγ4 T cells capable of co-producing IL-17A and IFNγ. Therefore, we used this model to evaluate the impact of aging on adaptive Vγ4 T cell responses elicited by foodborne infection.ResultsFoodborne Lm infection of female Balb/c and C57BL/6 mice led to an increased adaptive CD44hi CD27neg Vγ4 T cell response associated with aging. Moreover, Lm-elicited CD44hi CD27neg Vγ4 T cells maintained diverse functional subsets despite some alterations favoring IL-17A production as mice aged. In contrast to the documented susceptibility of aged mice to intravenous Lm infection, mice contained bacteria after foodborne Lm infection suggesting that elevated bacterial burden was not a major factor driving the increased adaptive CD44hi CD27neg Vγ4 T cell response associated with mouse age. However, CD44hi CD27neg Vγ4 T cells accumulated in naïve mice as they aged suggesting that an increased precursor frequency contributes to the robust Lm-elicited mucosal response observed. Body mass did not appear to have a strong positive association with CD44hi CD27neg Vγ4 T cells within age groups. Although an increased adaptive CD44hi CD27neg Vγ4 T cell response may contribute to foodborne Lm resistance of C57BL/6 mice aged 19 or more months, neither anti-TCRδ or anti-IL-17A treatment impacted Lm colonization after primary infection. These results suggest that γδTCR signaling and IL-17A are dispensable for protection after primary foodborne Lm infection consistent with the role of conventional T cells during the early innate immune response to Lm.ConclusionsLm-elicited adaptive Vγ4 T cells appear resistant to immunosenescence and memory Vγ4 T cells could be utilized to provide protective immune functions during enteric infection of aged hosts. As such, oral immunization might offer an efficient therapeutic approach to generate unconventional memory T cells in the elderly.

Abstract 503: Multiparameter Mass Cytometry Reveals The Unique Response Of NaïVe B Cell Cd27 - Subset With The Increase Of T-bet And Cd38 Expression After Radiation Therapy In Thoracic Cancer Patients

Cancer Radiation therapy (RT) induces cardiovascular disease (CVD) even when the heart is shealed or not irradiated, but there is a paucity of available preventive measures for RT-induced CVD. Ionizing radiation (IR) induces senescence, which was originally discovered to suppress tumorigenesis by inducing cell cycle blockade and necrosis, and positioned IR as pro-senescence cancer therapy. IR-induced senescence cells secrete cytokines, growth factors, and reactive oxygen species (ROS), becoming so called senescence associated secretory phenotype (SASP), and we hypothesize that SASP induction in immune cells cause CVD after RT. Although the involvement of DNA damage response (DDR), efferocytosis, and clonal hematopoiesis drivers (CHD) to SASP induction has been suggested, the exact mechanisms through which RT induces SASP in a specific cell type remains unclear. We characterize most of the major human immune cell lineages in a single assay using mass cytometery (CyTOF). We generated a CyTOF panel which includes antibodies against various senescence phenotype, DDR, efferocytosis, and CHD. We isolated peripheral blood mononuclear cells (PBMCs) before and 3 month after RT from 16 thoracic cancer patients. First, we found the frequency of only B cell subtype was decreased after RT. Second, we obtained 138 functional profiling subsets by unsupervised clustering with our antibody set, and found that T-bet expression was increased in the largest B cell subset of naïve B Cell (CD27 - ) Ki67 lo CD38 lo DNMT3a hi after RT, which showed the good correlation with p-p90RSK expression in the samples from pre-RT and post-RT. Lastly, the significant increase of CD38 expression in the subsets of naïve B cell (CD27 - ) and CD8 + T cell (EMRA) was detected. These data suggest the unique response of naïve B cell (CD27-) to RT with the increase of CD38 expression, and T-bet in the subset of B Cell (CD27 - ) Ki67 lo CD38 lo DNMT3a hi , and also the potential role of p90RSK activation in IR-induced T-bet expression. T-bet plays a role in developing the age-associated B cell (ABC), and the increase of CD38 expression promotes aging-related events. Therefore, the induction of T-bet and CD38 in naïve B (CD27 - ) cell after RT supports the novel role of naïve B cell in IR-induced SASP and subsequent CVD.

Migratory type 2 dendritic cells mediate mucosal Th17 response to gut commensal bacteria

Abstract Dendritic cells (DCs) are professional antigen-presenting cells equipped with MHC-restricted antigens, co-stimulations, and cytokines that effectively prime and differentiate naïve T cells into distinct functional subsets. The immune signals that DCs carry reflect the route of antigen uptake and the innate stimuli they received. In the mucosal tissues, owing to the great variety of foreign antigens and inflammatory cues, DCs are predominantly activated and migratory. The gut commensal bacteria contribute to immune health by educating the immune system at this unique location interfacing with the outside environment. In the small intestine, CD4 Th17 cells are abundant and play a critical role in mucosal defense against bacterial and fungal infections. We identified that the early priming step of commensal-driven Th17 cells is controlled by bona fide Zbtb46-expressing DCs. CCR7-dependent migration of DC2s from the small intestine to the mesenteric lymph nodes is essential for the activation of naïve CD4 T cells. The migratory DC2 population in the MLN are almost exclusively Esam+ cells. Single-cell RNA sequencing highlighted the abundance of co-stimulatory markers (CD40 and OX40) and chemokines (Ccl22 and Cxcl16) on MLN migratory DCs. Further resolution of MLN migratory DC2s revealed that the Th17-polarizing cytokine IL-6 colocalizes with DC2s expressing CD40, Ccl17, and Ccl22. Our study indicates that the mucosal Th17 cell response is regulated by a restricted subset of migratory DC2s in the gut draining lymph nodes. Supported by NIAID U01AI125859

Tumor-Associated Regulatory T Cells in Non-Small-Cell Lung Cancer: Current Advances and Future Perspectives.

Non-small-cell lung cancer (NSCLC) is one of the most threatening malignant tumors to human health, with the overall 5-year survival rate being less than 30%. Regulatory T cells (Tregs), a functional subset of T cells, maintain immunologic immunological self-tolerance and homeostasis. Accumulating evidence has uncovered their implicated roles in various cancers in recent years. In NSCLC, they are associated with staging, therapeutic efficacy, and prognosis by infiltrating in tissues and thereby attenuating immunologic anticancer effects in patients. Tumor-associated Tregs display distinct immune signatures in NSCLC compared to thymus-derived Tregs, playing an important role in remodeling the tumor microenvironment (TME). Targeting Tregs has become a novel direction for NSCLC patients, such as disrupting their immune-suppressive functions, blocking their trafficking into tumors, and inhibiting their development and/or activation. This review is aimed at elucidating the molecular mechanisms of tumor-associated Tregs in NSCLC and providing therapeutic targets relevant to Tregs.

Defective Monocyte Enzymatic Function and an Inhibitory Immune Phenotype in Human Immunodeficiency Virus-Exposed Uninfected African Infants in the Era of Antiretroviral Therapy.

BackgroundHuman immunodeficiency virus-exposed uninfected (HEU) infants are a rapidly expanding population in sub-Saharan Africa and are highly susceptible to encapsulated bacterial disease in the first year of life. The mechanism of this increased risk is still poorly understood. We investigated whether human immunodeficiency virus (HIV)-exposure dysregulates HEU immunity, vaccine-antibody production, and human herpes virus amplify this effect.MethodsThirty-four HIV-infected and 44 HIV-uninfected pregnant women were recruited into the birth cohort and observed up to 6 weeks of age; and then a subsequent 43 HIV-infected and 61 HIV-uninfected mother-infant pairs were recruited into a longitudinal infant cohort at either: 5–7 to 14–15; or 14–15 to 18–23 weeks of age. We compared monocyte function, innate and adaptive immune cell phenotype, and vaccine-induced antibody responses between HEU and HIV-unexposed uninfected (HU) infants.ResultsWe demonstrate (1) altered monocyte phagosomal function and B-cell subset homeostasis and (2) lower vaccine-induced anti-Haemophilus influenzae type b (Hib) and anti-tetanus toxoid immunoglobulin G titers in HEU compared with HU infants. Human herpes virus infection was similar between HEU and HU infants.ConclusionsIn the era of antiretroviral therapy-mediated viral suppression, HIV exposure may dysregulate monocyte and B-cell function, during the vulnerable period of immune maturation. This may contribute to the high rates of invasive bacterial disease and pneumonia in HEU infants.

Tranexamic acid alters the immunophenotype of phagocytes after lower limb surgery

BackgroundTranexamic acid (TXA) is an antifibrinolytic agent frequently used in elective surgery to reduce blood loss. We recently found it also acts as a potent immune-modulator in patients undergoing cardiac surgery.MethodsPatients undergoing lower limb surgery were enrolled into the “Tranexamic Acid in Lower Limb Arthroplasty” (TALLAS) pilot study. The cellular immune response was characterised longitudinally pre- and post-operatively using full blood examination (FBE) and comprehensive immune cell phenotyping by flowcytometry. Red blood cells and platelets were determined in the FBE and levels of T cell cytokines and the plasmin-antiplasmin complex determined using ELISA.ResultsTXA administration increased the proportion of circulating CD141+ conventional dendritic cells (cDC) on post-operative day (POD) 3. It also reduced the expression of CD83 and TNFR2 on classical monocytes and levels of circulating IL-10 at the end of surgery (EOS) time point, whilst increasing the expression of CCR4 on natural killer (NK) cells at EOS, and reducing TNFR2 on POD-3 on NK cells. Red blood cells and platelets were decreased to a lower extent at POD-1 in the TXA group, representing reduced blood loss.ConclusionIn this investigation we have extended our examination on the immunomodulatory effects of TXA in surgery by also characterising the end of surgery time point and including B cells and neutrophils in our immune analysis, elucidating new immunophenotypic changes in phagocytes as well as NK cells. This study enhances our understanding of TXA-mediated effects on the haemostatic and immune response in surgery, validating changes in important functional immune cell subsets in orthopaedic patients.

The subdifferentiability of functions convex with respect to the set of Lipschitz concave functions

A function defined on normed vector spaces X is called convex with respect to the set LĈ := LĈ (X,R ) ofLipschitz continuous classically concave functions (further, for brevity, LĈ -convex), if it is the upper envelope of some subset of functions from LĈ. A function f is LĈ -convex if and only if it is lower semicontinuous and bounded from below by a Lipschitz function. We introduce the notion of LĈ -subdifferentiability of a function at a point, i. e., subdifferentiability with respect to Lipschitz concave functions, which generalizes the notion of subdifferentiability of classically convex functions, and prove that for each LĈ -convex function the set of points at which it is LĈ -subdifferentiable is dense in its effective domain. The last result extends the well-known Brondsted – Rockafellar theorem on the existence of the subdifferential for classically convex lower semicontinuous functions to the more wide class of lower semicontinuous functions. Using elements of the subset LĈ θ ⊂ LĈ, which consists of Lipschitz continuous functions vanishing at the origin of X we introduce the notions of LĈ θ -subgradient and LĈ θ -subdifferential for a function at a point.The properties of LĈ -subdifferentials and their relations with the classical Fenchel – Rockafellar subdifferential are studied. Considering the set LČ := LČ (X,R ) of Lipschitz continuous classically convex functions as elementary ones we define the notions of LČ -concavity and LČ -superdifferentiability that are symmetric to the LĈ -convexity and LĈ -subdifferentiability of functions. We also derive criteria for global minimum and maximum points of nonsmooth functions formulated in terms of LĈ θ -subdifferentials and LČ θ -superdifferentials.